Regulation 2 - Definitions
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Regulation 2 - Definitions

 For the purpose of this chapter, unless expressly provided otherwise:

  1 Subdivision length (L s ) of the ship is the greatest projected moulded length of that part of the ship at or below deck or decks limiting the vertical extent of flooding with the ship at the deepest subdivision draught.

  2 Amidships is at the middle of the length (L).

  3 Aft terminal is the aft limit of the subdivision length.

  4 Forward terminal is the forward limit of the subdivision length.

  5 Length (L) is the length as defined in the International Convention on Load Lines in force.

  6 Freeboard deck is the deck as defined in the International Convention on Load Lines in force.

  7 Forward perpendicular is the forward perpendicular as defined in the International Convention on Load Lines in force.

  8 Breadth (B) is the greatest moulded breadth of the ship at or below the deepest subdivision draught.

  9 Draught (d) is the vertical distance from the keel line at:

  • .1 amidships, for ships subject to the provisions of regulation II-1/1.1.1.1; and

  • .2 the mid-point of the subdivision length (Ls), for ships not subject to the provisions of regulation II-1/1.1.1.1 but constructed on or after 1 January 2009;

to the waterline in question.

  10 Deepest subdivision draught (d s ) is the summer load line draught of the ship.

  11 Light service draught (d l ) is the service draught corresponding to the lightest anticipated loading and associated tankage, including, however, such ballast as may be necessary for stability and/or immersion. Passenger ships should include the full complement of passengers and crew on board.

  12 Partial subdivision draught (d p ) is the light service draught plus 60% of the difference between the light service draught and the deepest subdivision draught.

  13 Trim is the difference between the draught forward and the draught aft, where the draughts are measured at the forward and aft:

  • .1 perpendiculars respectively, as defined in the International Convention on Load Lines in force, for ships subject to the provisions of regulation II-1/1.1.1.1; and

  • .2 terminals respectively, for ships not subject to the provisions of regulation II-1/1.1.1.1 but constructed on or after 1 January 2009;

disregarding any rake of keel.

  14 Permeability (μ) of a space is the proportion of the immersed volume of that space which can be occupied by water.

  15 Machinery spaces are spaces between the watertight boundaries of a space containing the main and auxiliary propulsion machinery, including boilers, generators and electric motors primarily intended for propulsion. In the case of unusual arrangements, the Administration may define the limits of the machinery spaces.

  16 Weathertight means that in any sea conditions water will not penetrate into the ship.

  17 Watertight means having scantlings and arrangements capable of preventing the passage of water in any direction under the head of water likely to occur in intact and damaged conditions. In the damaged condition, the head of water is to be considered in the worst situation at equilibrium, including intermediate stages of flooding.

  18 Design pressure means the hydrostatic pressure for which each structure or appliance assumed watertight in the intact and damage stability calculations is designed to withstand.

  19 Bulkhead deck in a passenger ship means the uppermost deck:

  • .1 to which the main bulkheads and the ship's shell are carried watertight, for ships subject to the provisions of regulation II-1/1.1.1.1; and

  • .2 at any point in the subdivision length (Ls) to which the main bulkheads and the ship's shell are carried watertight and the lowermost deck from which passenger and crew evacuation will not be impeded by water in any stage of flooding for damage cases defined in regulation 8 and in part B-2 of this chapter, for ships not subject to the provisions of regulation II-1/1.1.1.1 but constructed on or after 1 January 2009.

The bulkhead deck may be a stepped deck. In a cargo ship not subject to the provisions of regulation II-1/1.1.1.1 but constructed on or after 1 January 2009, the freeboard deck may be taken as the bulkhead deck.

  20 Deadweight is the difference in tonnes between the displacement of a ship in water of a specific gravity of 1.025 at the draught corresponding to the assigned summer freeboard and the lightweight of the ship.

  21 Lightweight is the displacement of a ship in tonnes without cargo, fuel, lubricating oil, ballast water, fresh water and feedwater in tanks, consumable stores, and passengers and crew and their effects.

  22 Oil tanker is the oil tanker defined in regulation 1 of Annex I of the Protocol of 1978 relating to the International Convention for the Prevention of Pollution from Ships, 1973.

  23 Ro-ro passenger ship means a passenger ship with ro-ro spaces or special category spaces as defined in regulation II-2/3.

  24 Bulk carrier means a bulk carrier as defined in regulation XII/1.1.

  25 Keel line is a line parallel to the slope of the keel passing amidships through:

  • .1 the top of the keel at centreline or line of intersection of the inside of shell plating with the keel if a bar keel extends below that line, on a ship with a metal shell; or

  • .2 in wood and composite ships, the distance is measured from the lower edge of the keel rabbet. When the form at the lower part of the midship section is of a hollow character, or where thick garboards are fitted, the distance is measured from the point where the line of the flat of the bottom continued inward intersects the centreline amidships.

  26 2008 IS Code means the International Code on Intact Stability, 2008, consisting of an introduction, part A (the provisions of which shall be treated as mandatory) and part B (the provisions of which shall be treated as recommendatory), as adopted by resolution MSC.267(85), provided that:

  • .1 amendments to the introduction and part A of the Code are adopted, brought into force and take effect in accordance with the provisions of article VIII of the present Convention concerning the amendment procedures applicable to the Annex other than chapter I thereof; and

  • .2 amendments to part B of the Code are adopted by the Maritime Safety Committee in accordance with its Rules of Procedure.

  27 Goal-based Ship Construction Standards for Bulk Carriers and Oil Tankers means the International Goal-Based Ship Construction Standards for Bulk Carriers and Oil Tankers, adopted by the Maritime Safety Committee by resolution MSC.287(87), as may be amended by the Organization, provided that such amendments are adopted, brought into force and take effect in accordance with the provisions of article VIII of the present Convention concerning the amendment procedures applicable to the annex other than chapter I thereof.

 28 IGF Code means the International Code of safety for ships using gases or other low-flashpoint fuels as adopted by the Maritime Safety Committee of the Organization by resolution MSC.391(95), as may be amended by the Organization, provided that such amendments are adopted, brought into force and take effect in accordance with the provisions of article VIII of the present Convention concerning the amendment procedures applicable to the annex other than chapter I.

 29 Low-flashpoint fuel means gaseous or liquid fuel having a flashpoint lower than otherwise permitted under regulation II-2/4.2.1.1.


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